Spray with carbon nanotubes and method to spray the same

Abstract

A spray with carbon nanotubes and a method for spraying the spray to get an electron emitting source layer are provided. Choosing a proper and vaporizable solvent to disperse and suspend the carbon nanotubes scattered therein. To mixed up the carbon nanotubes with a binder or an additive to be the spray with a low viscosity. The solvent mixed is carried with a high-pressure air to spray uniformly on a negative conductive layer or a negative glass substrate, a thickness of a film sprayed by the solvent mixed can be adjusted and controlled by a spraying frequency thereof, and the film can be even and uniform and the carbon nanotubes can expose out easily to generate electrons and increase current density thereby in the spraying manner.

1. A spray with a plurality of carbon nanotubes adopted for a cathode of an electronic device, comprising:
 a plurality of carbon nanotubes having a predetermined length; 
 a solvent including Isoamyl Actrate, said solvent vaporizing within a range of predetermined temperatures to suspend the carbon nanotubes scattered therein; 
 a binder including glass powder having particles of a first size arranged in the solvent, said binder having a predetermined adhesive characteristic with predetermined interfaces resulting from a predetermined adhesive process between the carbon nanotubes and a surface of the cathode of the electronic device; and 
 an additive including a silver powder having silver particles of a second size, said additive reducing an impedance of the surface of the cathode of the electronic device; 
 wherein the spray includes approximately 20–25 weight percents of the binding, approximately 10–18 weight percents of the additive, and approximately 5–10 weight percent of the carbon nanotubes, 
 wherein the relationship between said predetermined length of the carbon nanotubes and said first size of the glass powder particles is approximately 10:9, and the relationship between said predetermined length of the carbon nanotubes and said second size of the silver particles is in the range between 10:3 and 10:5; 
 wherein the solvent with the carbon nanotubes is sprayed on the surface of the cathode of the electronic device repeatedly, and vaporizes within the range of predetermined temperatures, and 
 wherein after the predetermined adhesive process, the carbon nanotubes are dispersed on and adhesive to the surface of the cathode of the electronic device. 
 
     
     
       2. The spray of  claim 1 , further including a dispersant to disperse the additive, the binder and the carbon nanotubes uniformly therein. 
     
     
       3. The spray of  claim 2 , wherein the spray has a viscosity in a range between 15 and 17 centi poise (cPs). 
     
     
       4. The spray of  claim 1 , wherein the predetermined adhesive process includes a sintering process or a laser heating process. 
     
     
       5. A method for spraying a spray with carbon nanotubes on a cathode of an electronic device, the method comprising the steps of:
 (1) preparing a spray containing approximately 5–10 weight % of carbon nanotubes with a predetermined nanotube length, a solvent including Isoamyl Actrate, approximately 20–25 weight % of a binder having a glass powder with particles of a first size, and 10–18 weight % of an additive including a silver powder having silver particles of a second size, wherein the relationship between said predetermined nanotube length and said first size of the glass powder particles is approximately 10:9, and the relationship between said predetermined nanotube length and said second size of the silver particles is approximately in the range between 10:3 to 10:5; 
 (2) spraying the spray on a surface of the cathode of the electronic device; 
 (3) vaporizing the solvent within the range of predetermined temperatures; and 
 (4) repeating the steps (2) and (3) a predetermined number of times to obtain a film having a thickness within a predetermined range. 
 
     
     
       6. The method Of claimed as  claim 5  further including a step of: after the step (4), providing a predetermined adhesive process to create an electron emitting source layer. 
     
     
       7. The method of  claim 6 , wherein the predetermined adhesive process includes a sintering process or a laser heating process. 
     
     
       8. The method of  claim 6 , wherein the electron emitting source layer has a thickness arranged between 3 and 6 micrometers (μm). 
     
     
       9. The method of  claim 5 , wherein the spray is sprayed by a spray gun, the spray gun including a nozzle having a diameter arranged between 0.5 and 2.0 millimeters (mm), a high-pressure air valve having a flow rate ranged between 240 and 280 liters per minute (l/mm), and an adjustable solvent valve having a solvent flow rate controlled between 150 and 250 cubic centimeters per minute (cc/mm).